Product Uses Include
- Positive control for the study of microtubule binding proteins
- Investigation of the the effect of MAPs on microtubule dynamics
- Substrate for many protein kinases
MaterialA microtubule associated protein (MAP) fraction has been isolated from porcine brain by temperature induced tubulin polymerization followed by ionic exchange chromatography over a phosphocellulose matrix and salt elution (1, 2). The MAP fraction protein is supplied as a white lyophilized powder
PurityProtein purity is determined by scanning densitometry of Coomassie Blue stained protein on a 12% polyacrylamide gel. MAP2 constitutes 70% of the total protein (see Figure 1).
Figure 1: Microtubule associated protein fraction purity determination. A 10 µg sample of MAPF was separated by electrophoresis in a 12% SDS-PAGE system, and stained with Coomassie Blue.
Biological ActivityThe biological activity of the MAP fraction is determined by the ability of 0.1 mg/ml MAP fraction to enhance the polymerization rate (Vmax) of purified bovine brain tubulin (Cat. # TL238) in vitro. Stringent quality control ensures that the MAP fraction protein will stimulate tubulin polymerization at least five fold when compared to tubulin polymerization without MAP fraction.
Figure 2: Tubulin polymerization in the presence and absence of microtubule associated protein fraction. Tubulin polymerization reactions were carried out as in BK006 with 5% glycerol containing 2 mg/ml of pure bovine brain tubulin (Cat. # TL238) being polymerized in the presence and absence of 0.1 mg/ml MAP fraction protein.
References
- Vallee, R. B. 1982. J. Cell Biol. 92, 435-442
- Kuznetsov S. A., et al. 1981. FEBS Lett. 135, 241-244
For product Datasheets and MSDSs please click on the PDF links below. For additional information, click on the FAQs tab above or contact our Technical Support department at tservice@cytoskeleton.com
Cho, H. P., Liu, Y., Gomez, M., Dunlap, J., Tyers, M. and Wang, Y. (2005). The dual-specificity phosphatase CDC14B bundles and stabilizes microtubules. Mol. Cell. Biol. 25, 4541-4551.Satish, L., Blair, H. C., Glading, A. and Wells, A. (2005). Interferon-inducible protein 9 (CXCL11)-induced cell motility in keratinocytes requires calcium flux-dependent activation of μ-calpain. Mol. Cell. Biol. 25, 1922-1941.Teckchandani, A. M., Birukova, A. A., Tar, K., Verin, A. D. and Tsygankov, A. Y. (2005). The multidomain protooncogenic protein c-Cbl binds to tubulin and stabilizes microtubules. Exp. Cell Res. 306, 114-127.Mamoune, A., Luo, J. H., Lauffenburger, D. A. and Wells, A. (2003). Calpain-2 as a target for limiting prostate cancer invasion. Cancer Res. 63, 4632-4640.Nielsen, F. C., Nielsen, J., Kristensen, M. A., Koch, G. and Christiansen, J. (2002). Cytoplasmic trafficking of IGF-II mRNA-binding protein by conserved KH domains. J. Cell Sci. 115, 2087-2097.
Question 1: What proteins comprise the microtubule-associated protein fraction?
Answer 1: The MAPF is comprised of a mixture of MAP1, MAP2 and tau proteins.
Question 2: Has the MAPF product been shown to significantly affect tubulin polymerization?
Answer 2: Yes, the biological activity of the MAPF can be determined by the ability of 0.1 mg/ml MAPF to enhance the polymerization rate (Vmax) of purified porcine brain tubulin in vitro. Stringent quality control ensures that the MAPF proteins will stimulate tubulin polymerization approximately five fold when compared to tubulin polymerization without MAPF proteins.
If you have any questions concerning this product, please contact our Technical Service department at tservice@cytoskeleton.com
